Artificial teeth



Jan. 12, 1960 J. A. SAFFIR ARTIFICIAL TEETH Original Filed Dec. 6, 1955 wvll W Fig.2,

United States Patent O fiice application December 6, 1 955, Serial No.-

551,292, new Patent No. 2,888,747, dated June 2,

1959. Divided and this application September 24,

1958, Serial No. 763,035

6 Claims. (Cl. 32-8) This invention pertains to artificial teeth and more particularly relates to the anterior teeth, the present application being a divisional application of my copending application for Letters Patent, Serial No. 551,292, filed December 6, .1955, now Patent Number 2,888,747.

Numerous attempts have been made, in the past, by tooth manufacturers and dentists to construct artificial teeth to resemble natural living teeth in appearance and characteristics, but despite the most artistic efforts, the results have not been entirely availing or free from objection. Thus artificial teeth afforded by the prior art have generally been distinctly difierentiated from that of natural teeth in their appearance, and in addition their properties have not effectively simulated that of natural teeth, particularly with respect to the attendant sound effects, as during speech or mastication.

It is apparent that previous attempts to produce a more natural appearing tooth have not always been successful because of the failure to realize that when a living tooth was viewed, the view obtained was affected not only by the light reflected from the superficialsurfaces of the tooth but was affected-as well by the reflections from its own deepest structures. Moreover the discrepancy between artificial and natural teeth with respect to various physical properties, such as the aforesaid sound efiects, seemingly has not received appropriate consideration in the fabrication of artificial teeth, pursuant to the prior art.

The term living teeth as used in this application is meant to apply to teeth that have a vital pulp structure within their interiors. When the pulp no longer functions and has been replaced by a solid, as in root canal therapy,

. '2 Figure 1 is an elevational view of the labial-frontsurface of an upper left central incisor.

Figure 2 is a sectional view of the central incisor illustrated in Figure 1, taken along lines H-H'.

Figure 3 is a sectional longitudinal view of the central. incisor illustrated in Figure 1, taken along lines V--V'.'-

on of another central Figure 4 is a longitudinal incisor.

Like reference numerals refer to like parts throughout the several views.

For purposes of illustration a central incisor was used in all of the drawings; however, this invention can be applied to any tooth, anterior or posterior, upper or lower. In this connection, it will be understood that the artificial teeth within the purview of the present disclosure may desirably be of a derivation conforming with the usual practice in the art, embracing the use of such materials as ceramics, porcelain or synthetic resins, and adapted to afford the usually desired characteristics of translucency or transparency. However where merely the sound aspects of the present invention are contemplated, the aforesaid properties of translucency or transparency may not be a requisite for the material utilized in fabricating the artificial teeth.

Reference may now be had more particularly to Figure 1. This is the labial aspect of an upper left central incisorthat portion of an anterior tooth next to the the natural tooth loses some of its luster'and color and is referred to "as a dead tooth.

Often the vital pulp is referred to as the nerve structure in a tooth, but this term not being entirely correct,

it is not employed in this application. This living pulp in the center of a tooth is a soft, jelly-like mass composed mainly of liquid carrying blood and lymph vessels,

,nerves and connective tissue.

The pulp cavity is the term applied to the hollow space within a tooth that is occupied by the dental pulp, its outline generally similar to the. outline of the tooth.

The principal object of this invention is the obtainment of more natural looking teeth.

Another object is to obtain teeth that will also feel taken in conjunction with the accompanying drawings forming a part thereof.

lips. The labial surface desirably translucent or trans parent is designated at 1 and at 2 is the distal surface, the surface most distant from the median line of the dental arch when the tooth is in situ.

At 3 is the incisal 'or cutting surface, at 4 the mesial surface-the closest surface to the median line of the arch and at 5, the gingival or surface closest to the gum or tissues.

The dotted line 20 outlines an area or cavity 6 in the interior or core portion of the tooth which is filled with a colored or clear liquid.

The purpose of this insert orcore material is to aiiect' the reflected light from the tooth so as to give the tooth a more natural appearance as well as to alter the reso nance or sound efiects of the tooth so as to greatly deaden or substantially obviate the unnatural sound efiects at-' embarrassing click, often to an extent where they withdraw socially, limit their conversations, and hesitate to eat in public places. There are cases where such withdrawal has puzzled other members of the family and worried them into calling in a psychiatrist, but it can be understood that such a clicking which can be heard to the annoyance of people in the vicinity, can be nosier and more discomforting to the person producing it since it originates within a few inches of the inner car.

This central portion 6 of liquid tends to absorb and cushion sharp sound efiects, attributable to theuse of artificial teeth and lower their pitch inasmuch as it acts very similar to ones own natural tooth which also had a semi-solid, jelly-like mass in its center and which did not click, due, in part, to this deadener of sound.

Central portion may be filled with quite a variety of liquids depending on the needs.

The size of the core may vary. In teeth for young people it should be large and can, in widthmesiodistally-equal up to two thirds the width of the too andfollowtheshapeoftbetccth. Inl

- Patented Jan. 12, 1960 -'vall it g irowi. its thickness need not be over one of the thickness of the portion of the tooth it is replacing.

As the age of the patient increases, the core can be made smaller and smaller until it is no more than a narrow slit two to six millimeters in width and two to eight eters in length and approximately two nullimetera in thickness inasmuch as this filler can influence the final color of the tooth and its reaction to natural and artific al light, it is important to be guided by that consideration in choosing the color of this inset.

The filling materials rescent in ultra violet light by adding any of the well known fluorescent producing compounds, as, for example, uranium oxide added to .5 %one-half of one percentbyweight of the core material. The addition of zinc sulphate also causes fluorescence as well as certain dyes, some of which are mentioned later.

Figure 2 is a sectional view of the central incisor in Figure 1, taken along the line HH'. The core 6 1s filled with a liquid and need not be regular in its outhne but can have bulges or points along any margin, as shown at 8 and 9. Because the labial wall of this tooth is translucent, a special line or spot efiect will result wherever such bulges or irregularities, 8 and 9, are created.

Figure 3 is a sectional view of the central incisor in Figure 1 taken at the lines V'-V'. A gingival opening llll leads through a duct 1135, through the core opening 12,1nto the core 6. In a porcelain tooth, such as this, it is usually best to fill the core with liquid after the tooth is complete with the metal retention pins 1 0. After the core is filled, the duct 13 from the opening 111 to core mouth or opening'l2 is filled with any type of sealing cementorganic or inorganic-such as zinc oxyphosphate, or plastic cement, such as the cellulose acetone cements or high fusing waxes or pitches. Or-small porcelain, plastic, wood-like, or metal inserts or wedges can be cemented or screwed into place in the area 113. Any means to keep the core tightly sealed during the processing of the denture and during use, is, of course, satisfactory.

In adjusting these teeth, the dentist must avoid grinding too close or into the core and it is suggested that any such grinding of the incisal, for example, should not pass the point 22 (Figures 1, 3, 4), since this will avoid any necessity for rescaling the core, or, as in the case where liquid is apt to be spilled, the replenishment and rescaling of liquid core material will be obviated.

In accordance with the indication hereinabove, the core may comprise any liquid material desirably nontoxic, which affords the reflective and/or acoustic characteristics applicable to such illustrative substances, exemplihad by water, alcohol, liquid petrolatum, glycerin, or any suitable liquid, when they are enveloped by the body portion of an artificial tooth, as an internal cavity thereof.

'lhe core area or' cavity may be filled with the core material at the factory or by the dentist and because it thus becomes possible to afiect the color of the tooth by the color of the core material, a' large variety of shades is easily manipulable.

Any coloring solution or paste may be used but the number of possible coloring materials, both dyes and pigments being so numerable, only a few are mentioned.

For young peoples teeth, a bright redthe color of a normal, living, healthy pulp is desirable. A dilute M to 1% solution of Rhodamine B may be used when a red may be up to two=thirds of the length of for the core may be made fiuov till amount of methylene blue can be added and where bluish green is desired, methylene green. lit green in desired, naphthol green maybe incorporated; for purple,

methyl violet. Eosin may be used where pink is desired,

especially for fiourescene as eosin is a flourescent dye.

Water, alcohol, glycerine, glycerol, liquid petrola,

acetone, 2. glycol, and any or the hundreds of solvents suitable for any particular dye or pigment may be used.

The point of caution to be observed, however, is

that no chemical or dye should be employed that can cause injury or harm to the mouth or body in the amount present in the core of the tooth if such substance should accidently be spilled in the mouth; e.g., if a tooth were to break during mastication. I

A cross section of a plastic central incisor is illustrated in Figure 4. The plasticcore d can be placed in position during processing; If the materials used to form the tooth are polymerizable and the material used to form the core is non-polymerizable-or polymerizes only to the extent of becoming jelly-like-then the tooth molds can be packed at the same time and the core will be permanently fixed in position when the act of polymerization is complete.

7 If a completely liquid core is desired for a plastic tooth, then the tooth can be constructed as illustrated in Figure 3- or a solid walled capsule of cellophane or similar substance containing the liquid core can be onclosed in the tooth mold prior to curing, as in Figure 4.

Although I have described a method of practicing my invention I contemplate that numerous and extensive departures may be made therefrom without departing from the spirit of my invention and the scope of the appended claims.

The invention is hereby claimed as follows:

1. An artificial tooth comprising a body portion enveloping a cavity internally thereof and a core material sealed within said cavity, said core material being adapted to allord sound-reflective characteristics simulative to a natural tooth in use, said core material consisting of a liquid.

2. An artificial tooth comprising a body portion en veloping a cavity internally thereof, said body portion being light-translucent and a core material sealed within said cavity, said core material being adapted to afiord sound and light-reflective characteristics simulative of a natural tooth in use, said core material consisting of a liquid,

3. An artificial tooth comprising a body portion enveloping a cavity internally thereof, at least the outer surface of the body portion being light-translucent, and a core material sealed within said cavity, said core material being adapted to afiord sound and light-reflective characteristics simulative of a natural tooth in use, said core material consisting of a liquid.

4. An artificial tooth comprising a body portion enveloping a cavity internally thereof, said cavity having an opening at a surface of said body portion, a-core material within said cavity, said core material being adapted to afford sound and light-reflective characteristics simulative of a natural tooth in use, said core material consisting of a liquid, and said opening being provided with means therein for sealing the same to thereby hermetically enclose the core material.

5. An artificial tooth as in claim 4, wherein at least the outer surface of the body. portion is light-translucent.

6. An artificial tooth as in claim 3, wherein the core material comprises a liquid of predetermined coloration.

References (Cited in the file of this patent UNITED STATES PATENTS 589,383 Dennett Aug. 31, 1s97 1,246,999 Pinches Nov. 20, 1917 ronniGN PATENTS 1,047,362. France July 22, 1953 

